Method of producing a remote imaging array

ABSTRACT

The present invention provides a method of producing a remote imaging array. A first imaging sensor, having a focal axis, is coupled to a housing, having a curvilinear array axis, along the curvilinear array axis. A second imaging sensor, having a focal axis, is coupled to the housing along the curvilinear array axis adjacent to the first imaging sensor, such that the focal axes of the first and second imaging sensors intersect one another at an intersection area. A third imaging sensor, having a focal axis, is coupled to the housing along a curvilinear array axis adjacent to the first imaging sensor, opposite the second imaging sensor, such that the focal axes of the first and third imaging sensors intersect one another at the intersection area. The second and third imaging sensors&#39; fields of view are aligned with target areas opposite their respective positions in the housing.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of prior U.S. application Ser. No.10/229,626 filed on Aug. 28, 2002.

TECHNICAL FIELD OF THE INVENTION

The present invention relates, generally, to the field of remote imagingtechniques and, more particularly, to an imaging system providinghigh-resolution digital imaging over very large fields of view.

BACKGROUND OF THE INVENTION

Remote imaging is a broad-based technology having a number of diverseand extremely important practical applications—such as geologicalmapping and analysis, military surveillance and planning, andmeteorological forecasting. Aerial and satellite-based photography andimaging are especially useful remote imaging techniques that have, overrecent years, become heavily reliant on the collection and processing ofdigital image data. Spatial data—characterizing real estate improvementsand locations, roads and highways, environmental hazards and conditions,utilities infrastructures (e.g., phone lines, pipelines), andgeophysical features—can now be collected, processed, and communicatedin a digital format to conveniently provide highly accurate mapping andsurveillance data for various civilian and military applications (e.g.,dynamic GPS mapping).

A major challenge facing some such remote imaging applications is one ofimage resolution. Certain applications require very high imageresolution—often with tolerances of inches. Depending upon theparticular system used (e.g., aircraft, satellite, or space vehicle), anactual digital imaging device may be located anywhere from severalhundred feet to several miles above its target, resulting in a verylarge scale factor. Providing images with very large scale factors, thatalso have resolution tolerances of inches, poses a challenge to even themost robust imaging system.

Orthophotography is one approach that has been used in an attempt toaddress this problem. In general, orthophotography renders an image of atarget by compiling varying images of the target. Typically, in aerialimaging applications, a digital imaging device that has a finite rangeand resolution records images of fixed subsections of a target areasequentially. Those images are then aligned according to sequence torender a composite of a target area. Usually, conventional systems mustmake some trade-off between resolution quality and the size of area thatcan be imaged. If the system is designed to provide high-resolutiondigital images, then the field of view (FOV) of the imaging device istypically small. Numerous imaging iterations must be performed in orderto orthographically render an image of a large area. If the systemprovides a larger FOV, then usually the resolution of the digital imageis decreased and the distortion is increased.

Some conventional digital imaging systems have attempted to addressthese issues with large-scale single lens cameras. These camerastypically comprise a very large primary optical lens, behind which anumber of optical sensors are embedded. The characteristics of theseconfigurations, especially the optical properties of the primary lens,tend to render images of very small cross sectional area. Generally,sensors in these systems have either identical or coinciding lines ofsight. Such systems are generally inefficient when images with wide FOVare desired. Furthermore, such systems are usually very costly. Rapiddevelopment of new sensor technologies renders these systems obsolete orrequires that the systems have cumbersome and costly upgrades ormodifications.

Other conventional systems have attempted to address the shortcomings ofsuch primary lens configurations through the use of divergent sensorarrays. Usually, optical sensors are outwardly mounted along a convexbrace or housing such that their focal axes diverge outwardly from theimaging device. Based on the intended scale factor for the images, theindividual sensors in the array can be disposed such that their focalplanes adjoin or slightly overlap at a desired distance from the targetarea. Although such a configuration can provide a wider FOV for imaging,it is still limited in application. The sensor arrays must be mountedwithin a host aircraft or spacecraft, and thus require a portal in thecraft through which to obtain image data. Large sensor arrays requirelarge portals to provide proper optical access for all the divergingsensors in the array. In many cases, however, large portal spaces areimpractical, if not impossible, to provide within the small confines ofa host craft. Furthermore, larger portals allow a relatively high degreeof light backscatter in the array, causing ghost images and degradingthe overall quality and reliability of the images obtained.

There is, therefore, a need for an imaging system that providesefficient and versatile imaging for different FOVs, especially verylarge FOVs while maintaining image quality and clarity.

SUMMARY OF THE INVENTION

The present invention provides an imaging system having a compound arrayof imaging sensors disposed such that their focal axes converge,intersect, and thereafter diverge. Individual imaging sensors can bedisposed within a housing or a host craft in a concave or retinalconfiguration, with non-coinciding lines of sight. Depending upon theconfiguration of the housing or host craft, a small aperture, portal oriris may be formed in the housing, and the array positioned in relationto the aperture, portal or iris, such that the point of intersection ofthe focal axes coincides with the aperture, portal or iris—the size ofwhich can thus be minimized. Thus, a small aperture in the housing orcraft may provide optical access to the target area for a large numberof sensors. The individual sensors are disposed, and may be selectivelyadjusted, to have adjoining or overlapping lines of sight within thetarget area, resulting in a wide collective FOV of the target area. Theimaging array of the present invention thus provides images with verylittle image distortion. The present invention further eliminates theneed for cumbersome, expensive primary lenses.

In one embodiment, the present invention provides a remote imagingsystem for producing an image of a target that has a housing; a firstimaging sensor, coupled to the housing having a first focal axis; and atleast one secondary imaging sensor, coupled to the housing and offsetfrom the first imaging sensor, each having a focal axis.

In one embodiment, the present invention provides a system for producingan image of a target viewed through an aperture. The system preferablycomprises a housing, having preferably three or more imaging sensorscoupled to the housing. Each imaging sensor produces a portion of theimage. Each imaging sensor has a focal axis passing through theaperture, such that the focal axes of all imaging sensors intersectwithin an intersection area.

The present invention also provides a system for producing an image of atarget viewed through an aperture that includes a housing, having afirst imaging sensor centrally coupled to the housing. The first imagingsensor has a first focal axis passing through the aperture. A secondimaging sensor is coupled to the housing and offset from the firstimaging sensor along an axis, and has a second focal axis passingthrough the aperture and intersecting the first focal axis within anintersection area. A third imaging sensor is coupled to the housing andoffset from the first imaging sensor along the axis, opposite the secondimaging sensor. The third imaging sensor has a third focal axis passingthrough the aperture and intersecting the first focal axis within theintersection area.

The present invention also provides a method of producing a remoteimaging array. A camera housing having a curvilinear housing axis isprovided. A primary imaging sensor is coupled to the housing along thecurvilinear housing axis, with the sensor's focal axis projectingoutwardly from the housing. Secondary imaging sensors are coupled to thehousing along the curvilinear housing axis on alternate sides of theprimary imaging sensor, and aligned such that their focal axes intersectthe focal axis of the primary sensor at an intersection area and theirfields of view align with target areas opposite their respectivepositions in the housing.

In addition, the present invention provides a compound camera systemthat comprises a first support member, that is preferably concave,having an apex of curvature at its top. A second support member isangularly displaced with respect to the first support member. The secondsupport member is adapted to intersect the apex of the first supportmember. A primary imaging sensor is centrally disposed along the concavesurface of the first support member, having a primary focal axisprojecting orthogonally from the first support member. A plurality ofsecondary imaging sensors are disposed along the concave surfaces of thefirst and second supports, at alternating angular intervals from theprimary imaging sensor to create two arrays of sensors. The secondaryimaging sensors are aligned such that their focal axes intersect withthe primary focal axis in defined intersection area.

In an alternative embodiment of the invention, a remote imaging systemfor producing an image of a target is provided comprising a housing; animaging sensor, coupled to the housing by electro-mechanicallyadjustable attachments; and an actuator that moves the imaging sensor tomultiple imaging positions. In yet another alternative, a remote imagingsystem for producing an image of a target is provided with a housing; animaging sensor, coupled to the housing; a moveably attached mirrorsystem coordinated with the imaging sensor; and an actuator to move themirror system to multiple positions to permit imaging of the terrain.

Other features and advantages of the present invention will be apparentto those of ordinary skill in the art upon reference to the followingdetailed description taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, and to show by way ofexample how the same may be carried into effect, reference is now madeto the detailed description of the invention along with the accompanyingfigures in which corresponding numerals in the different figures referto corresponding parts and in which:

FIG. 1A illustrates a cross-sectional view of one embodiment of animaging array according to the present invention;

FIG. 1B is an illustration of a bottom view of the array of FIG. 1A,taken along line 1B-1B of FIG. 1A;

FIG. 2 illustrates one embodiment of a remote imaging system accordingto the present invention;

FIG. 3 illustrates a cross-sectional view of one embodiment of animaging array according to the present invention;

FIG. 4A illustrates a bottom view of one embodiment of an imaging arrayaccording to the present invention;

FIG. 4B illustrates a perspective view of the imaging array of FIG. 4A;

FIG. 5 illustrates a cross-sectional view of one embodiment of animaging array according to the present invention;

FIG. 6 illustrates a bottom view of one embodiment of an imaging arrayaccording to the present invention; and

FIG. 7 illustrates one embodiment of a remote imaging system accordingto the present invention.

DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the presentinvention are discussed in detail below, it should be appreciated thatthe present invention provides many applicable inventive concepts, whichcan be embodied in a wide variety of specific contexts. The specificembodiments discussed herein are merely illustrative of specific ways tomake and use the invention and do not limit the scope of the invention.

The preferred embodiment of the present invention provides an imagingsystem having a compound array of imaging sensors disposed such thattheir focal axes converge, intersect, and thereafter diverge. Individualimaging sensors can be disposed within a host craft in a concave orretinal configuration, with non-coinciding lines of sight. Dependingupon the configuration of the host craft, a small aperture, portal oriris may be formed in the craft, and the array positioned in relation tothe aperture, portal or iris, such that the point of intersection of thefocal axes coincides with the aperture, portal or iris—the size of whichcan thus be minimized. Thus, a small aperture in the craft may provideoptical access to the target area for a large number of sensors. Theindividual sensors are disposed, and may be selectively adjusted, tohave adjoining or overlapping lines of sight within the target area,resulting in a wide collective FOV of the target area. The imaging arrayof the present invention thus provides high-resolution images with verylittle image distortion. The present invention further eliminates theneed for cumbersome, expensive primary lenses.

The present invention is applicable for use in a number of photographicand imaging applications, and is particularly applicable to aerialphotography and imaging. Therefore, for purposes of explanation andillustration, the present invention is hereafter described within thecontext of an aerial imaging application. It should be understood,however, that those of skill in the art will, upon reference to thisdescription, be able to apply the principles and teachings of thepresent invention in a wide variety of imaging systems—from personaldigital cameras to manufacturing conveyor inspection systems, satellitesand other spacecraft-based surveillance systems.

Referring now to FIGS. 1A and 1B, one embodiment of the presentinvention is provided as an illustrative example. FIG. 1A depicts acamera array assembly 100 airborne over target 102 (e.g., terrain). Forillustrative purposes, the relative size of assembly 100, and therelative distance between it and terrain 102, are not depicted to scalein FIG. 1A. Assembly 100 comprises a housing 104 within which imagingsensors 106, 108, and 110 are disposed along a concave curvilinear arrayaxis 112, forming an array 113. In all embodiments, the radius ofcurvature of array axis 112 may be altered dramatically, providing theability to effect very subtle or very drastic degrees of concavity inaxis 112. Alternatively, array axis 112 may be completely linear—havingno curvature at all. Imaging sensors 106, 108, and 110 couple to housing104, either directly or indirectly, by attachment members 114.Attachment members 114 may comprise a number of fixed or dynamic,permanent or temporary, connective apparatus. For example, members 114may comprise simple welds, removable clamping devices, orelectro-mechanically controlled universal joints.

As depicted in FIGS. 1A and 1B, housing 104 comprises a simple enclosureinside of which sensors 106, 108, and 110 are disposed. Sensors 106,108, and 110 couple, via members 114, either collectively to a singletransverse cross member 116, or individually to lateral cross members118, disposed between opposing walls of housing 104. In alternativeembodiments, housing 104 may itself comprise only a supporting crossmember of concave curvature to which sensors 106, 108, and 110 couple,via members 114. In other embodiments, housing 104 may comprise a hybridcombination of enclosure and supporting cross member. In the preferredembodiment, housing 104 has an aperture 120 formed in its surface,between the sensors 106, 108, 110 and target 102. However, as mentionedabove, the housing 104 structure may be varied significantly, includingbeing a minimal structure that is open on the lower side, such that noaperture 120 is formed.

Depending upon the specific type of host craft, aperture 120 maycomprise only a void, or it may comprise a protective screen or windowto maintain environmental integrity within housing 104. Optionally,aperture 120 may comprise a lens or other optical device to enhance oralter the nature of the images recorded by the sensors. Aperture 120 isformed with a size and shape sufficient to provide sensors 106, 108, and110 with proper lines of sight to a target region 122 on terrain 102.

Sensors 106, 108 and 110 are disposed within or along housing 104 suchthat the focal axes of all sensors converge and intersect each otherwithin an intersection area 132 bounded by aperture 120. Depending uponthe type of image data being collected, the specific sensors used, andother optics or equipment employed, it may be necessary or desirable tooffset the intersection area 132 or point of convergence above or belowaperture 120. Sensors 106, 108 and 110 are separated from each other atangular intervals, which are preferably equal. The exact angle ofdisplacement between the sensors may vary widely depending upon thenumber of sensors utilized and on the type of imaging data beingcollected. In alternative embodiments, the angular displacement betweensensors may be unequal—so as to provide a desired image offset oralignment. Depending upon the number of sensors utilized, and theparticular configuration of the array 113, the focal axes 124, 130, 136of all sensors may intersect at exactly the same point, or may intersectat a plurality of points, all within close proximity to each other andwithin the intersection area 132 defined by aperture 120. As the numberof sensors and the ruggedness of the environment in which assembly 100is employed increase, the precise alignment necessary to yield only asingle intersection point 132 may be very difficult, if not impossible,to maintain. It is not necessary to maintain a single intersectionpoint, as long as all axes converge and intersect in close proximity toone another such that the size and shape of aperture 120 need not bealtered to provide a proper line of sight to the sensors 106, 108, 110.

As depicted in FIG. 1A, sensor 108 is centrally disposed within housing104 along array axis 112. Sensor 108 has a focal axis 124, directedorthogonally from housing 104 to align the sensor's line of sight withimage area 126 of region 122. Sensor 106 is disposed within housing 104along array axis 112, adjacent to sensor 108. Sensor 106 is aligned suchthat its line of sight coincides with image area 128 of region 122, andsuch that its focal axis 130 converges with and intersects axis 124 atintersection point 132. Sensor 110 is disposed within housing 104adjacent to sensor 108, on the opposite side of array axis 112 fromsensor 106. Sensor 108 is aligned such that its line of sight coincideswith image area 134 of region 122, and such that its focal axis 136converges with and intersects axes 124 and 130 at intersection point132. Sensors 106, 108 and 110, a well as subsequently described sensors,may comprise a number of imaging devices including individual cameras,infrared sensors, seismic sensors, photo detectors and photocells.Further, the infrared sensors may be multispectral or hyperspectral.Each sensor may comprise an individual imaging device, or a group ofsensors. Sensors 106, 108 and 110 are preferably of a homogenous nature,but may comprise a combination of varied imaging devices.

From point 132, axes 124, 130 and 136 diverge. Thus, sensors 106 and 110are alternately disposed within housing 104 along array axis 112 suchthat each sensor's focal axis converges upon point 132, crosses focalaxis 124, and aligns its field of view with a target area opposite itsrespective position in the array 113—resulting in a “cross-eyed”,retinal relationship between the sensors and the imaging target(s). Ifmembers 114 are of a permanent and fixed nature (e.g., welds), then thespatial relationship between aperture 120, the sensors, and their linesof sight remain fixed—as will the spatial relationship between imageareas 126, 128 and 134. Such a configuration may be desirable in, forexample, a satellite surveillance application where assembly 100 willremain at an essentially fixed distance from region 122. The positionand alignment of the sensors is set such that areas 126, 128 and 134provide full imaging coverage of region 122.

In other applications, however, it may be desirable to selectivelyadjust, either manually or by remote automation, the position oralignment of the sensors so as to shift, narrow or widen areas 126, 128and 134, and thereby enhance or alter the images collected by assembly100. One such embodiment is illustrated now by reference to FIG. 2.

An airborne imaging system 200 is depicted, and comprises an arrayassembly 100 in addition to a flight control system 202, a cameracontrol system 204, and an image processing system 206. System 206receives imaging data from the imaging sensors within assembly 100 viacommunicative links 208. Links 208 may comprise direct, physicalconnectors (e.g., wires, cables) between assembly 100 and system 206, orthey may comprise communications connections (e.g., wirelesstransceivers). System 206 may be located within the same host craft(e.g., airplane) as assembly 100, or may be remotely located apart fromthe host craft (e.g., satellite monitoring station). Imaging data fromassembly 100 is transmitted to system 206, where it may be monitored,analyzed, processed or stored. If a change is desired in the imagingdata being collected by assembly 100, system 206 may initiate changes inthe position of the host craft, assembly 100, the individual sensorswithin assembly 100, or any combination thereof.

If a change in the position of the host craft is desired, system 206provides notification of the desired change to flight control system 202via communicative link 210 (e.g., change altitude). Link 210 maycomprise a direct, physical connector (e.g., wire, cable) or an indirectcommunications connection (e.g., wireless transceivers). System 202 maycomprise a number of collocated or remote navigation systems orcombinations thereof—from a pilot onboard an aircraft to a remote flightcontrol system on a satellite.

If a change in the position of assembly 100, with respect to the hostcraft or housing 104, is desired, system 206 provides notification ofthe desired change to system 202 via link 210, which communicates thenecessary adjustment to assembly 100 via link 212. Link 212 may comprisea communicative link (e.g., cable, wireless transceivers) that notifiesassembly 100 of the desired change (e.g., raise, lower, rotate), leavingassembly 100 to actuate the change via internal or externally associatedmechanical systems (e.g., hydraulics). Alternatively, link 212 maycomprise a mechanical link that directly effects the desired changeitself. Link 210 may comprise a direct, physical connector (e.g., wire,cable) or an indirect communications connection (e.g., wirelesstransceivers).

If a change in the position of one or more of the individual sensors inassembly 100 is desired, system 206 provides notification of the desiredchange to camera control system 204 via communicative link 214 (e.g.,change position of focal intersection point 132). Link 214 may comprisea direct, physical connector (e.g., wire, cable), or an indirectcommunications connection (e.g., wireless transceivers). Individualsensors within assembly 100 receive notification of desired changes(e.g., change position, change angle) via links 216, which communicatethe necessary adjustments to members 114. Links 216 may comprisecommunicative links (e.g., cables, wireless transceivers) that notifymembers 114 of changes desired (e.g., raise, lower, rotate), leavingmembers 114 to actuate the changes via internal or externally associatedmechanical systems (e.g., hydraulics). Alternatively, links 216 maycomprise mechanical links that directly effect the desired changes.System 204 may comprise a number of control devices and systems,disposed within assembly 100, located externally but proximal toassembly 100, or remote from assembly 100, or combinations thereof.

Although depicted as separate systems in FIG. 2, systems 202, 204, and206 may, depending upon the application and host craft or housing 104configuration, comprise separate functionalities of a single controlsystem deployed within the host craft. Consider for example, acomputer-based, self-contained, electro-mechanical control system onboard a manned surveillance aircraft. In other embodiments (e.g., asurveillance satellite), certain elements (e.g., system 202 and 204) maybe deployed within the host craft (e.g., the satellite) while otherelements (e.g., system 206) are remotely located (e.g., at a monitoringfacility). Other combinations of the systems described above are alsocomprehended by the present invention.

Referring now to FIG. 3, another embodiment of the present invention isprovided as an illustrative example. FIG. 3 depicts a camera arrayassembly 300, comprising a housing 302 within which a plurality ofimaging sensors 304 are disposed along a concave curvilinear array axis306. Assembly 300 is essentially identical in composition, construction,and operation to assembly 100, with the exception of having a greaternumber of imaging sensors 304 disposed therein. The sensors 304 coupleto housing 302, either directly or indirectly, by attachment members(not shown). The sensors 304 may couple collectively to a singletransverse cross member 116, individually to lateral cross members 118,or directly to housing 302. Housing 302 comprises an aperture 308 formedin its surface, between the sensors 304 and a target below (not shown).Depending upon the specific type of imaging application and host craft,aperture 308 may comprise a void, a protective screen or window, or alens or other optical device. Aperture 308 is formed with a size andshape sufficient to provide sensors 304 proper line of sight to a targetregion.

Sensors 304 are disposed within or along housing 302 such that the focalaxes 310 of all sensors 304 converge and intersect each other within thearea defined by aperture 308. Again, the focal axes 310 of all sensors304 may intersect at exactly one intersection point 312, or mayintersect at a plurality of intersection points all within closeproximity to each other and within the area defined by aperture 308. Asdepicted in FIG. 3, the sensors 304 are disposed within housing 302along array axis 306 in a “cross-eyed” fashion. One sensor is centrallydisposed, with focal axis 310 directed orthogonally from housing 302.The other sensors 304 are alternately disposed within housing 302 alongaxis 306 such that the focal axis 310 of each sensor 304 converges uponpoint 312, crosses the focal axis of the central sensor, and aligns itsfield of view with a target area opposite its respective position in thearray. Again, the sensors 304 may comprise a number of imaging devicesincluding individual cameras, infrared sensors, seismic sensors, photodetectors and photocells—either as individual devices or as a group.Preferably sensors 304 are all of a homogenous nature, but they maycomprise a combination of varied imaging devices. Again, the relativepositions and angles of the sensors 304 may be fixed, or may be manuallyor mechanically adjustable.

The embodiments described thus far are particularly useful forcollecting and processing imaging data extremely wide, rectilinearstrips. Using orthophotographic techniques, the rectilinear image can becombined with subsequent images taken along the host craft's flight pathto create a composite image having an extremely large FOV. The presentinvention provides further embodiments that may lessen or eliminate theneed for orthophotographic techniques, depending upon the application.

One such embodiment is illustrated now with reference to FIGS. 4A and4B. FIGS. 4A and 4B depict a camera array assembly 400. Except for thedifferences described hereafter, assembly 400 is similar in composition,construction, and operation to assemblies 100 and 300. As depicted inFIGS. 4A and 4B, assembly 400 comprises first imaging element or array402 and second array 404. Arrays 402 and 404 are configured as parallelsub-arrays of imaging sensors, longitudinally offset by a desiredmargin. Array 402 comprises housing 406, within which imaging sensors408, 410, 412, and 414 are disposed in accordance with the presentinvention along concave curvilinear array axis 416. Array 404 compriseshousing 418, within which imaging sensors 420, 422, and 424 are disposedin accordance with the present invention along concave curvilinear arrayaxis 426. Elements 402 and 404 are disposed within a host craft in closelongitudinal proximity to each other, having axes 416 and 426,preferably in parallel alignment, to collect and provide imaging datafor a common target region (not shown).

Sensors 408, 410, 412, 414, 420, 422, and 424 are preferably similar inshape and size, but may be of differing shapes and sizes, providing theability to retrieve an image of the target region having a desired shapeor size. Individual sensors having specific shapes and sizes can bedisposed and manipulated to focus on image areas that adjoin or overlapin desired patterns. As depicted in FIGS. 4A and 4B, sensor 422 iscentrally disposed within housing 418 along array axis 426 such that itsfocal axis is directed from housing 418 through intersection area 428.Area 428 is a point or small region through which the focal axes of allthe imaging sensors within 418 align. Arrays 402 and 404 may be disposedwithin assembly 400 such that area 428 is orthogonally centered withrespect to sensor 422, whereas the array 402 is orthogonal centered onarea 429 (as depicted in FIG. 4A).

Sensors 420 and 424, similar in shape and size to sensor 422, arealternately disposed within housing 418 along array axis 426 such thatthe focal axis of each converges upon area 428, crosses the focal axisof sensor 422, and aligns its field of view with a target area oppositeits respective position in the array 404.

Sensors 410 and 412, similar in shape and size to sensor 422, arealternately disposed within housing 406 along array axis 416 such thatthe focal axis of each converges upon area 429 and align their field ofview with a target area opposite their respective position in the array404. Sensors 410 and 412 are disposed within housing 406 such that theirfields of view align with the gaps between sensors 420, 422, and 424.

Sensors 408 and 414, preferably of similar size and shape as sensor 422,are alternately disposed within housing 406 along array axis 416 suchthat the focal axis of each converges upon area 429. Sensors 410 and 412are disposed within housing 406, outside sensors 410 and 412, such thattheir fields of view align outside all sensors in element 404. Theslight offset in the sensors of elements 402 and 404 provide assembly400 with the ability to produce images having customizable FOVs. Inalternative embodiments, any number of arrays, containing any number ofsensors having various shapes and sizes, may be combined to provideimaging data on any desired target region. In such embodiments, theresulting offset in images collected by the sub-arrays of assembly 400may be resolved with one another, using a variety of image processingtechniques, to provide a single high-resolution image.

In still another embodiment of the present invention, depicted in FIG.5, a cross-sectional view of a camera array assembly 500 is illustrated.Except for the differences described hereafter, assembly 500 is similarin composition, construction, and operation to assemblies 100, 300 and400. Assembly 500 comprises a first compound member 502, shown in sideview, and a second compound member 504, shown in cross-sectional view.Member 502 comprises a curvilinear support member or array, to which anumber of imaging sensors 508 are disposed along its concave side. Aprimary imaging sensor 506 is centrally disposed along the concave sideof member 502, with its focal axis directed orthogonally downward fromassembly 500.

A number of imaging sensors 508 are also disposed along the concave sideof member 502, in a “cross-eyed” fashion. The cross-eyed sensors 508 arealternately disposed along member 502 such that the focal axis of eachsensor 508 converges upon and crosses the focal axis of sensor 506 at asingle intersection area (not shown), and aligns its field of view witha target area opposite its respective position in the array.

Member 504 also comprises a curvilinear support member or array, towhich a number of imaging sensors 510 are disposed along its concaveside. Member 504 is preferably formed orthogonal to 502 and is of a sizeand curvature sufficient to match the arch of member 502. Member 504 maybe formed or disposed such that its concave surface contacts, or evencouples to, the convex surface of member 502 at its apex. Alternatively,member 504 may bridge over member 502, clearing its apex within proximaldistance thereto. Imaging sensors 510 are disposed along the concaveside of member 504, in a “cross-eyed” fashion. The cross-eyed sensors510 are alternately disposed along member 502 such that the focal axisof each sensor 510 converges upon and crosses the focal axis of sensor506 at the single intersection area, and aligns its field of view with atarget area opposite its respective position in the array.

The distance and angular offsets in the sensors of elements 502 and 504,coupled with the shared intersection area, provide assembly 500 with theability to produce images having customizable FOVs. Depending upon theelements and sensors utilized, assembly 500 may be deployed to producestereoscopic images. In alternative embodiments, any number of elements,containing any number of sensors having various shapes and sizes, may becombined to provide imaging data on any desired target region.

Another embodiment, enhancing the advantages of assembly 500, isillustrated in FIG. 6. FIG. 6 depicts a camera array assembly 600 from abottom view. Assembly 600 comprises a primary compound curvilinearmember or array 602, and a plurality of compound curvilinear members 604that are formed of size and curvature sufficient to offset and arch overor contact member 602 at various angular intervals. Any number ofmembers 604 may be employed, and may be so numerous as to form a domestructure for mounting sensors. The angular displacement between themembers 604 varies depending upon the size of the members and thedesired imaging characteristics. For example, assembly 600 may comprisetwo support members in an orthogonal (i.e. 90°) relationship with oneanother. Another assembly, having three support members, may beconfigured such that the angular displacement between members is 60°.

A primary imaging sensor 606 is centrally disposed along the concaveside of member 602, with its focal axis directed orthogonally downwardfrom assembly 600. A number of imaging sensors 608 are disposed, inaccordance with the teachings of the present invention, along theconcave sides of members 602 and 604 in a “cross-eyed” fashion. Thecross-eyed sensors 608 are alternately disposed along members 602 and604 such that the focal axis of each sensor preferably converges uponand crosses the focal axis of sensor 606 at a single intersection area(not shown), and aligns its field of view with a target area oppositeits respective position in the array. Depending upon the shape and sizeof sensors 608, assembly 600 provides the ability to produce imageshaving customizable FOVs, of a generally circular nature. Depending uponthe elements and sensors utilized, assembly 600 may be deployed toproduce stereoscopic images. In alternative embodiments, any number ofelements, containing any number of sensors having various shapes andsizes, may be combined to provide imaging data on any desired targetregion.

Referring now to FIG. 7, one embodiment of a camera array assembly 700in accordance with the present invention is depicted. Assembly 700 issimilar in composition, construction, and operation to assemblies 100,300 and 400. Assembly 700 comprises first imaging element or array 702,second imaging array 704, and third imaging array 706. Array 704 isconfigured as a primary sensor array, disposed within assembly 700 suchthat the focal axis 708 of its primary sensor 710 is directed downwardlyfrom assembly 700, orthogonal to target area 712 along terrain 714.Assembly 700 is disposed within a host craft that moves, with respect toterrain 714, along flight path 716. Elements 702, 704 and 706 areconfigured within assembly 700 as sub-arrays of imaging sensors. Element702 is offset, with respect to flight path 716, ahead of element 704 andoffset there from by angular offset 718. Similarly, element 706 isoffset, with respect to flight path 716, behind element 704 and offsetthere from by angular offset 720. Angular offset 718 is selected suchthat the focal axis 722 of primary sensor 724 on element 702 is directeddownward to target area 712, forming angle 732. Angular offset 720 isselected such that the focal axis 728 of primary sensor 730 on element706 is directed downward to target area 712, forming angle 726. Angularoffsets 718 and 720 are preferably equal, although they may be skewed toprovide a desired imaging effect. The focal axes of the other individualsensors along elements 702, 704 and 706 form similar angularrelationship to target area 712 and one another, subject to theirrespective positions along the elements. Imaging data is characterized,on a pixel-by-pixel basis, in terms of the positional and angularrelationships described above.

Knowing the positional and angular relationships among elements 702,704, 706, and their constituent individual sensors, imaging datacollected by assembly 700 are processed to provide high-resolutionorthographic images. In alternative embodiments, the elements andsensors are configured, and the data collected is processed, to providehigh-resolution stereographic images. The size and resolution of theimaging array may be altered in accordance with the present as describedabove.

In another embodiment of the present invention, the camera assembly 700is modified and comprises one imaging element or array 702, configuredas a primary sensor array, as described above, and having an actuator ormotor (not shown) that rocks or moves the array 402 back and forth.Alternatively, the actuator may flip or rotate the array 702. In onepreferred embodiment, the array 702 is directed to forward, downward,and backward positions. In another embodiment of the invention, thearray 702 is stationary, and a moving mirror system is used inconjunction with the mirror system to collect sensor data from multiplepositions of the terrain 714.

The embodiments and examples set forth herein are presented to bestexplain the present invention and its practical application and tothereby enable those skilled in the art to make and utilize theinvention. However, those skilled in the art will recognize that theforegoing description and examples have been presented for the purposeof illustration and example only. The description as set forth is notintended to be exhaustive or to limit the invention to the precise formdisclosed. Many modifications and variations are possible in light ofthe above teaching without departing from the spirit and scope of thefollowing claims.

1. A method of producing a remote imaging array, comprising the stepsof: providing a camera housing, having a curvilinear array axis;coupling a first imaging sensor, having a focal axis, to the housingalong the curvilinear array axis; coupling a second imaging sensor,having a focal axis, to the housing along the curvilinear array axisadjacent to the first imaging sensor, such that the focal axes of thefirst and second imaging sensors intersect one another at anintersection area; coupling a third imaging sensor, having a focal axis,to the housing along a curvilinear array axis adjacent to the firstimaging sensor, opposite the second imaging sensor, such that the focalaxes of the first and third imaging sensors intersect one another at theintersection area; and aligning the second and third imaging sensors'fields of view with target areas opposite their respective positions inthe housing.
 2. The method of claim 1, wherein the step of aligning thefirst, second and third imaging sensors further comprises aligning theirfocal axes to intersect within an intersection area.
 3. The method ofclaim 1, wherein the steps of aligning the first, second and thirdimaging sensors further comprises aligning their focal axes to intersectat an aperture.
 4. The method of claim 1, wherein the steps of aligningthe first, second and third imaging sensors further comprises aligningtheir focal axes to intersect at a target.
 5. The method of claim 1,wherein the steps of aligning the first, second and third imagingsensors further comprises aligning their focal axes to intersect at apoint.
 6. The method of claim 1, wherein the step of aligning the secondand third imaging sensors further comprises aligning their focal axes tobe parallel to each other.
 7. The method of claim 1, wherein the stepsof aligning the second and third imaging sensors further comprisesaligning their focal axes to diverge from one another.
 8. The method ofclaim 1, wherein the steps are repeated to produce a plurality ofimaging arrays.
 9. A method of producing a remote imaging array,comprising the steps of: providing a camera housing, having acurvilinear array axis; coupling a first imaging array, having a focalaxis, to the housing along the curvilinear array axis; coupling a secondimaging array, having a focal axis, to the housing along the curvilineararray axis adjacent to the first imaging array, such that the focal axesof the first and second imaging arrays intersect one another at anintersection area; coupling a third imaging array, having a focal axis,to the housing along a curvilinear array axis adjacent to the firstimaging array, opposite the second imaging array, such that the focalaxes of the first and third imaging arrays intersect one another at theintersection area; and
 10. aligning the second and third imaging arrays'fields of view with target areas opposite their respective positions inthe housing.
 11. The method of claim 9, wherein the step of aligning thefirst, second and third imaging arrays further comprises aligning theirfocal axes to intersect within an intersection area.
 12. The method ofclaim 9, wherein the steps of aligning the first, second and thirdimaging arrays further comprises aligning their focal axes to intersectat an aperture.
 13. The method of claim 9, wherein the steps of aligningthe first, second and third imaging arrays further comprises aligningtheir focal axes to intersect at a target.
 14. The method of claim 1,wherein the steps of aligning the first, second and third imaging arraysfurther comprises aligning their focal axes to intersect at a point. 15.The method of claim 9, wherein the step of aligning the second and thirdimaging arrays further comprises aligning their focal axes to beparallel to each other.
 16. The method of claim 9, wherein the steps ofaligning the second and third imaging arrays further comprises aligningtheir focal axes to diverge from one another.